The human immunodeficiency viris (hiv) is a bloodborne pathogen that is spread by

Which of the following statements is true about the relationship between genetic variation and natural selection? a. genetic variation must be present in a population before natural selection can act on it. b. genetic variation arises in a population as a result of natural selection. c. natural selection can act on a population whether there is genetic variation within the population or not. d. after natural selection acts on a population, the amount of genetic variation in the population always increases.

Why were the results whit just water so much different than the trials with the detergent ?

What did you notice about the onion root tip cells that you saw at 40x power?